#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <limits.h>
#define OJ_TEST 0
#define LOCAL_TEST 0

#define M 901

static int max(int a, int b){ return a>b?a:b; }
static int min(int a, int b) { return a<b?a:b; }

static void solve(void){
	unsigned n, ans, i, m;
	while(scanf("%u", &n), n){
		ans = 0;
		m = sqrt(n);
		if(m*m==n || (m+1)*(m+1)==n) ans=1;
		printf("%s\n", ans?"yes":"no");
	}

}
#if OJ_TEST
	int main(int ac, char *av[]){
		solve();
		return 0;
	}
#elif  LOCAL_TEST
	void run(void){
		solve();
	}

#else

#endif
